ML20236W580
| ML20236W580 | |
| Person / Time | |
|---|---|
| Site: | Oyster Creek |
| Issue date: | 10/14/1987 |
| From: | Long R GENERAL PUBLIC UTILITIES CORP. |
| To: | NRC OFFICE OF ADMINISTRATION & RESOURCES MANAGEMENT (ARM) |
| Shared Package | |
| ML20236V972 | List: |
| References | |
| PNS-87-0105, PNS-87-105, NUDOCS 8712080098 | |
| Download: ML20236W580 (3) | |
Text
_.
g GPU Nuclear Corporation s.
gggf Post Office Box 388 Route 9 South Forked River, New Jersey 08731-0388 609 971-4000 Wnter's Direct Dial Number:
October 14, 1987 PNS-87-0105 Revised:
November
, 1987 l
U.S. Nuclear Regulatory Commission Document Control Desk Washington, DC 20555
Dear Sir:
Subject:
Oyster Creek Nuclear Generating Station Docket No. 50-219 Safety Limit Violation Revised Page 2 By letter dated September 20, 1987, GPU Nuclear detailed the safety 11ait violation which occurred at the Oyster Creek Nuclear Generating station on September 11, 1987. The cover letter to that submittal specified operator error as the cause of the violation.
This letter is being written to supplement the root cause analysis provided and further delineate why the operator error occurred.
The safety limit which was violated requires at least two recirculation loops to be operable (i.e., suction valve and discharge valve open) at all times unless the reactor vessel head is off and the reactor is flooded to a level above the Main Steam nozzles.
The plant had B and C recirculation loops l
operabl e.
A, D, and E recirculation loops had their respective discharge valves shut.
Due to an imminent loss of cooling water to the Recirculation Pumps (RCP), the operator commenced securing RCPs B and C.
In accordance with the normal operating procedure when the plant is at power, he started closing the loop discharge valve prior to de-energizing the pump.
In this I
off-normal plant configuration, this sequence of actions caused a violation of the safety limit due to personnel error.
The root cause of the personnel error was that the operator failed to implement the procedure for securing RCPs on a loss of RBCCW.
Abnormal Operating Procedure 2000-ABN-3200.19 "RBCCW Failure Response" specifies that the RCPs are to be secured and the recirculation suction and discharge valves verified open (to prevent violation of the safety limit).
Had the operator implemented this procedure, the safety limit violation would not have occurred.
As committed in our September 20, 1987 letter, the importance of adherence to approved procedures will be stressed to the operators prior to plant restart.
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G GPU Muclear Corporation is a subscary of the General Public Utdities Corporation
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PSN-87-0105 October 14, 987 Revised November
, 1937 l
l Alarm response procedure 2000-RAP-3024.01 which directs the operator to l
procedure 2000-ABN-3200.19 was reviewed for clarification and a few minor revisions were issued. As committed in our letter of September 20, 1987, trairing on this procedure and its new revisions will be completed prior _to restart.
During this event, the operator did not consult 2000-ABN-3200.19 prior to closing the recirculation discharge valve.
Consulting an abnormal or emergency procedure prior to taking requisite immediate actions is not required during an emergency.
Operators are trained to implement memorized imediate actions and then consult the procedure to verify the completeness of those actions which were taken.
A contributory cause to this event was that the training of operators on recirculation pump securing, like the operating procedure, had been structured towards normal operating conditions.
As stated in our September 20, 1987 letter, GPUN believes that the sense of urgency to secure the RCP associated with the impending loss of the RCP cooling source, Reactor Building Closed Cooling Water (RBCCW), was uppermost in the operator's mind when the violation occurred.
In this event, the operator reacted instinctively to execute the practice which was routine to him without appropriate consideration of the existing plant conaitions or recirculation loop availability.
Had his " hands on" trainicg at the Basic Principles Simulator or the Full Scale Simulator more stringently challenged him on off-normal recirculation pump operations, the proper action may have been taken.
Similarly, if he had been drilled more completely on the RBCCW failure response procedure, his " instinctive" response may have been the correct one for the existing off-normal conditions.
Operating Procedure 301, which includes normal recirculation pump securing, was revised to more appropriately place a caution statement immediately preceding the section on RCP securing.
Training on the Basic Principles Simulator and the Full Scope Simulator was modified to specifically include RCP operations from off-normal conditions. As committed in our September LO,1987 letter, training on Procedure 301 and its revision, and training on the Basis Principles Simulator will be completed prior to restart.
The modified training on the Full Scope Simulator has been initiated and is projected for completion by November 30, 1987.
Finally, a contributory cause to this event was the safety limit itself.
Subsequent to the 1979 event when the safety limit was submitted and approved, GPUN determined that one loop, not two, is required to provide adequate communication between the core and annulus region for a worst case analysis.
Had a Technical Specification Change Request been submitted to more appropriately define the recirculation loop requirements as a one loop Limiting Condition for Operation vice a two loop safety limit, the actual significance of this event would have been more clearly reflected in the Technical Specifications.
PNS-87-0105 October 14, 1987
. As committed in our September 20, 1987 letter, a Technical Specification Change Request is being evaluated for submittal to more appropriately define the significance of isolating a fourth recirculation loop.
Additionally, a review of the Technical Specifications has been initiated to determine if any other specific items could be more appropriately defined. And finally, as a member of the Boiling Water Reactor Owner's Group, GPUN is participating in a long term Technical Specification upgrade program where many utilities are sharing experience and knowledge to improve Technical Specifications throughout the industry as a whole.
If any further information is required, please contact Mr. John Rogers of my staff at (609)971-4893.
Very truly yours, R. L. Long Vice President & Director Planning & Nuclear Safety RLL/JR/dmd(0385A) cc: Dr. Thomas E. Murley, Director Mr. Lee H. Bettenhausen Office of Nuclear React 6r Regulation Chief, Projects Branch No.1 U.S. Nuclear Regulatory Commission U.S. Nuclear Regulatory Commission Washington, DC 20555 Region I 631 Park Avenue Mr. William T. Russell, Administrator King of Prussia, PA 19406 Region I U.S. Nuclear Regulatory Commission Mr. S. Collins 631 Park Avenue Chief, Projects Branch No.1 King of Prussia, PA 19406 U.S. Nuclear Regulatory Commission Region I NRC Resident Inspector 631 Park Avenue Oyster Creek Nuclear Gen. Station King of Prussia, PA 19406 Forked River, NJ 08731 Mr. B. Boger Mr. Alex Dromerick, Jr.
U.S. Nuclear Regulatory Commission U.S. Nuclear Regulatory Commission Division of Reactor Projects I/II 7920 Norfolk Avenue 7920 Norfolk Avenue, Phillips Bldg.
Phillips Building, Mail Stop 314 Bethesda, MD 20014 Bethesda, MD 20014 i